Naturally occurring ruthenium is composed of seven stable isotopes. Additionally 34 radioactive isotopes have been discovered. Of these radioisotopes the most stable are 106Ru with a half-life of 373.59 days 103Ru with a half-life of 39.26 days and 97Ru with a half-life of 2.9 days.45

Fifteen other radioisotopes have been characterized with atomic weights ranging from 89.93 u (90Ru) to 114.928 u (115Ru). Most of these have half-lives that are less than five minutes except 95Ru (half-life: 1.643 hours) and 105Ru (half-life: 4.44 hours).45

The primary decay mode before the most abundant isotope 102Ru is electron capture and the primary mode after is beta emission. The primary decay product before 102Ru is technetium and the primary mode after is rhodium.45 Occurrence See also: category:Ruthenium minerals

Ruthenium is exceedingly rare and is the 74th most abundant metal on Earth.6 This element is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small but commercially important quantities are also found in pentlandite extracted from Sudbury Ontario Canada and in pyroxenite deposits in South Africa. The native form of ruthenium is a very rare mineral (Ir replaces part of Ru in its structure).78 Production Mining Roughly 12 tonnes of Ru is mined each year with world reserves estimated as 5000 tonnes.6 The composition of the mined platinum group metal (PGM) mixtures varies in a wide range depending on the geochemical formation. For example the PGMs mined in South Africa contain on average 11% ruthenium while the PGMs mined in the USSR contain only 2% based on research dating from 1992.910 Ruthenium like the other platinum group metals is obtained commercially as a by-product from nickel and copper mining and processing as well as by the processing of platinum group metal ores. During electrorefining of copper and nickel noble metals such as silver gold and the platinum group metals including selenium and tellurium settle to the bottom of the cell as anode mud which forms the starting point for their extraction.78 In order to separate the metals they must first be brought into solution. Several methods are available depending on the separation process and the composition of the mixture; two representative methods are fusion with sodium peroxide followed by dissolution in aqua regia and dissolution in a mixture of chlorine with hydrochloric acid.1112 Osmium ruthenium rhodium and iridium can be separated from platinum and gold and base metals by their insolubility in aqua regia leaving a solid residue. Rhodium can be separated from the residue by treatment with molten sodium bisulfate. The insoluble residue containing Ru Os and Ir is treated with sodium oxide in which Ir is insoluble producing water-soluble Ru and Os salts. After oxidation to the volatile oxides RuO4 is separated from OsO4 by precipitation of (NH4)3RuCl6 with ammonium chloride or by distillation or extraction with organic solvents of the volatile osmium tetroxide.13 Hydrogen is used to reduce ammonium ruthenium chloride yielding a powder.14 The first method to precipitate the ruthenium with ammonium chloride is similar to the procedure that Smithson Tennant and William Hyde Wollaston used for their separation. Several methods are suitable for industrial scale production. In either case the product is reduced using hydrogen yielding the metal as a powder or sponge that can be treated using powder metallurgy techniques or by argon-arc welding.15 From used nuclear fuels Main article: Synthesis of precious metals Ruthenium is a fission product of uranium-235. Each kilo of fission products contains significant amounts of the lighter platinum group metals and also ruthenium. Used nuclear fuel might be a possible source for ruthenium. The complicated extraction is expensive and the also present radioactive isotopes of ruthenium would make a storage for several half-lives of the decaying isotopes necessary. This makes this source of ruthenium unattractive and no large-scale extraction has been started.161718 Chemical compounds See also: Category:Ruthenium compounds The oxidation states of ruthenium range from 0 to +8 and 2. The properties of ruthenium and osmium compounds are often similar. The +2 +3 and +4 states are the most common. The most prevalent precursor is ruthenium trichloride a red solid that is poorly defined chemically but versatile synthetically.14 Oxides Ru can oxidize to ruthenium tetroxide RuO4 a strong oxidizing agent with structure analogous to osmium tetroxide. Other examples are ruthenium(IV) oxide (RuO2 oxidation state +4) dipotassium ruthenate (K2RuO4 +6) and potassium perruthenate (KRuO4 +7).19 Coordination and organometallic complexes Main article: Organoruthenium chemistry Tris(bipyridine)ruthenium(II) chloride. Ruthenium forms a variety of coordination complexes. Examples are the many pentammine derivatives Ru(NH3)5Ln+ which often exist in both Ru(II) and Ru(III). Derivatives of bipyridine and terpyridine are numerous best known being the luminiscent tris(bipyridine)ruthenium(II) chloride. Ruthenium form a wide range compounds with carbon-ruthenium bonds. Ruthenocene is analogous to ferrocene structurally but exhibits distinctive redox properties. A large number of complexes of carbon monoxide are known the parent being triruthenium dodecacarbonyl. The analogue of iron pentacarbonyl ruthenium pentacarbonyl is unstable at ambient conditions. Ruthenium trichloride carbonylates (reacts with carbon monoxide) to give mono- and diruthenium(II) carbonyls from which many derivatives have been prepared such as RuHCl(CO)(PPh3)3 and Ru(CO)2(PPh3)3 (Roper's complex). Heating solutions of ruthenium trichloride in alcohols with triphenylphosphine gives tris(triphenylphosphine)ruthenium dichloride (RuCl2(PPh3)3) which converts to the hydride complex chlorohydridotris(triphenylphosphine)ruthenium(II) (RuHCl(PPh3)3).14 In the area of fine chemical synthesis Grubbs' catalyst is used for alkene metathesis.20 History Though naturally occurring platinum containing all six platinum group metals was used for a long time by pre-Columbian Americans and known as a material to European chemists from the mid-16th century it took until the mid-18th century for platinum to be identified as a pure element. The discovery that natural platinum contained palladium rhodium osmium and iridium took place in the first decade of the 19th century.21 Platinum in alluvial sands of Russian rivers gave access to raw material for use in plates and medals and for the minting of ruble coins starting in 1828.22 Residues of platinum production for minting were available in the Russian Empire and therefore most of the research on them was done in Eastern Europe. It is possible that the Polish chemist Jdrzej niadecki isolated element 44 (which he called "vestium") from platinum ores in 1807. He published his discovery in Polish language in article "Rosprawa o nowym metallu w surowey platynie odkrytym" in 1808. His work was never confirmed however and he later withdrew his claim of discovery.6 Jns Berzelius and Gottfried Osann nearly discovered ruthenium in 1827.23 They examined residues that were left after dissolving crude platinum from the Ural Mountains in aqua regia. Berzelius did not find any unusual metals but Osann thought he found three new metals pluranium ruthenium and polinium. This discrepancy led to a long-standing controversy between Berzelius and Osann about the composition of the residues.24 In 1844 the Russian scientist Karl Klaus showed that the compounds prepared by Gottfried Osann contained small amounts of ruthenium which Klaus had discovered the same year.21 Klaus isolated ruthenium from the platinum residues of the rouble production while he was working in Kazan University Kazan.24 Klaus showed that ruthenium oxide contained a new metal and obtained 6 grams of ruthenium from the part of crude platinum that is insoluble in aqua regia.24 The name derives from Ruthenia the Latin word for Rus' a historical area which includes present-day western Russia Ukraine Belarus and parts of Slovakia and Poland. Karl Klaus used the name proposed by Gottfried Osann in 1828. He chose the element's name in honor of his birthland as he was born in Tartu Estonia which was at the time a part of the Russian Empire.2125 Applications Because of its ability to harden platinum and palladium ruthenium is used in platinum and palladium alloys to make wear-resistant electrical contacts. In this application only thin plated films are used to achieve the necessary wear-resistance. Because of its lower cost and similar properties compared to rhodium15 the use as plating material for electric contacts is one of the major applications.726 The thin coatings are either put on by electroplating27 or sputtering.28 Ruthenium dioxide lead and bismuth29 ruthenates the latter with perovskite crystal structure30 are used in thick film chip resistors.31 The first two applications account for 50% of the ruthenium consumption.6 There are only a few alloys used other than with elements of the platinum group metals. Ruthenium is always used in small quantities in those alloys to improve certain properties of the alloys. One example is the use of small amounts of ruthenium to increase the stability of gold in jewelry. The beneficial effect on the corrosion resistance of titanium alloys led to the development of a special alloy containing 0.1% ruthenium .32 Ruthenium is also used in some advanced high-temperature single-crystal superalloys with applications including the turbine blades in jet engines. Several nickel based superalloy compositions are described in the literature. Among them are EPM-102 (with 3 % Ru) and TMS-162 (with 6 % Ru) both containing 6 % rhenium33 as well as TMS-13834 and TMS-174.3536 Fountain pen nibs are frequently tipped with alloys containing ruthenium. From 1944 onward the famous Parker 51 fountain pen was fitted with the "RU" nib a 14K gold nib tipped with 96.2% ruthenium and 3.8% iridium.37 Ruthenium is a component of mixed-metal oxide (MMO) anodes used for cathodic protection of underground and submerged structures and for electrolytic cells for chemical processes such as generating chlorine from salt water.38 The fluorescence of some ruthenium complexes is quenched by oxygen which has led to their use as optode sensors for oxygen.39 Ruthenium red (NH3)5Ru-O-Ru(NH3)4-O-Ru(NH3)56+ is a biological stain used to stain polyanionic molecules such as pectin and nucleic acids for light microscopy and electron microscopy.40 The beta-decaying isotope 106 of ruthenium is used in radiotherapy of eye tumors mainly malignant melanomas of the uvea.41 Ruthenium-centered complexes are being researched for possible anticancer properties.42 Ruthenium unlike traditional platinum complexes shows greater resistance to hydrolysis and more selective action on tumors. NAMI-A and KP1019 are two drugs undergoing clinical evaluation against metastatic tumors and colon cancers. Catalysis Ruthenium is a versatile catalyst. Hydrogen sulfide can be split by light by using an aqueous suspension of CdS particles loaded with ruthenium dioxide. This may be useful in the removal of H2S in oil refineries and other industrial processing facilities.43 Organometallic ruthenium carbene and alkylidene complexes have been found to be highly efficient catalysts for olefin metathesis a process with important applications in organic and pharmaceutical chemistry.44 Solar energy conversion Some ruthenium complexes absorb light throughout the visible spectrum and are being actively researched in various potential solar energy technologies. For example Ruthenium-based compounds have been used for light absorption in dye-sensitized solar cells a promising new low-cost solar cell system.45 Data storage Chemical vapor deposition of ruthenium (CVD) is used as a method to produce thin films of pure ruthenium on substrates. These films show promising properties for the use in microchips and for the giant magnetoresistive read element for hard disk drives.46 Ruthenium was also suggested as a possible material for microelectronics because its use is compatible with semiconductor processing techniques.47 Exotic materials Many ruthenium based oxides show very unusual properties such as a Quantum Critical Point behavior48 exotic superconductivity49 and high temperature ferromagnetism.50 References "Ruthenium: ruthenium(I) fluoride compound data". OpenMOPAC.net. http://openmopac.net/datanormal/ruthenium(i)%20fluoridejmol.html. 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United States Geological Survey USGS. http://minerals.usgs.gov/minerals/pubs/commodity/platinum/myb1-2006-plati.pdf. Retrieved 2008-09-16.  a b "Commodity Report: Platinum-Group Metals". United States Geological Survey USGS. http://minerals.usgs.gov/minerals/pubs/commodity/platinum/mcs-2008-plati.pdf. Retrieved 2008-09-16.  Hartman H. L.; Britton S. G. ed (1992). SME mining engineering handbook. Littleton Colo.: Society for Mining Metallurgy and Exploration. p. 69. ISBN 9780873351003. http://books.google.com/idWm6QMRaX9C4C&pgPA69.  Harris Donald C.; Cabri L. J. (1973). "The nomenclature of the natural alloys of osmium iridium and ruthenium based on new compositional data of alloys from world-wide occurrences". The Canadian Mineralogist 12 (2): 104112. http://canmin.geoscienceworld.org/cgi/content/abstract/12/2/104.  Renner H.; Schlamp G.; Kleinwchter I.; Drost E.; Lschow H. M.; Tews P.; Panster P.; Diehl M.; Lang J.; Kreuzer T.; Kndler A.; Starz K. A.; Dermann K.; Rothaut J.; Drieselman R. (2002). "Platinum group metals and compounds". Ullmann's Encyclopedia of Industrial Chemistry. Wiley. doi:10.1002/14356007.a21075.  Seymour R. J.; O'Farrelly J. I. (2001). "Platinum-group metals". Kirk Othmer Encyclopedia of Chemical Technology. Wiley. doi:10.1002/0471238961.1612012019052513.a01.pub2.  Gilchrist Raleigh (1943). "The Platinum Metals.". Chemical Reviews 32 (3): 277372. doi:10.1021/cr60103a002.  a b c Cotton Simon (1997). Chemistry of Precious Metals. Springer-Verlag New York LLC. pp. 120. ISBN 0751404136. http://books.google.com/id6VKAs6iLmwcC&pgPA2.  a b Hunt L. B.; Lever F. M. (1969). "Platinum Metals: A Survey of Productive Resources to industrial Uses". Platinum Metals Review 13 (4): 126138. http://www.platinummetalsreview.com/pdf/pmr-v13-i4-126-138.pdf.  Kolarik Zdenek; Renard Edouard V. (2005). "Potential Applications of Fission Platinoids in Industry". 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Platinum Metals Review 40 (2): 5461. http://www.platinummetalsreview.com/pdf/pmr-v40-i2-054-061.pdf.  Bondarenko Yu. A.; Kablov E. N.; Surova V. A.; Echin A. B. (2006). "Effect of high-gradient directed crystallization on the structure and properties of rhenium-bearing single-crystal alloy". Metal Science and Heat Treatment 48: 360. doi:10.1007/s11041-006-0099-6.  "Fourth generation nickel base single crystal superalloy". http://sakimori.nims.go.jp/catalog/TMS-138-A.pdf.  Koizumi Yutaka et al.. "Development of a Next-Generation Ni-base Single Crystal Superalloy". Proceedings of the International Gas Turbine Congress Tokyo November 27 2003. http://nippon.zaidan.info/seikabutsu/2003/00916/pdf/igtc2003tokyots119.pdf.  Walston S.; Cetel A.; MacKay R.; O'Hara K.; Duhl D.; Dreshfield R.. "Joint Development of a Fourth Generation Single Crystal Superalloy". http://gltrs.grc.nasa.gov/reports/2004/TM-2004-213062.pdf.  Mottishaw J. (1999). "Notes from the Nib WorksWhere's the Iridium". 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H.-B.; Daniels M.; Luttmer J. D. (1998). "Etching Byproducts of Ruthenium Wafers Using Various Etching Chemistries". Environmental issues in the electronics/semiconductor industries and: Electrochemical/photochemical methods for pollution. The Electrochemical Society. pp. 1014. ISBN 9781566771993.  Perry R.; Kitagawa K.; Grigera S.; Borzi R.; MacKenzie A.; Ishida K.; Maeno Y. (2004). "Multiple First-Order Metamagnetic Transitions and Quantum Oscillations in Ultrapure Sr3Ru2O7". Physical Review Letters 92. Bibcode 2004PhRvL..92p6602P. doi:10.1103/PhysRevLett.92.166602.  Maeno Yoshiteru; Rice T. Maurice; Sigrist Manfred (2001). "The Intriguing Superconductivity of Strontium Ruthenate". Physics Today 54: 42. doi:10.1063/1.1349611. http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/49957/1/PTO000042.pdf.  Shlyk Larysa; Kryukov Sergiy; Schpp-Niewa Barbara; Niewa Rainer; De Long Lance E. (2008). "High-Temperature Ferromagnetism and Tunable Semiconductivity of (Ba Sr)M2xRu4xO11 (M Fe Co): A New Paradigm for Spintronics". Advanced Materials 20: 1315. doi:10.1002/adma.200701951.  External links Wikimedia Commons has media related to: Ruthenium Look up ruthenium in Wiktionary the free dictionary. Nano-layer of ruthenium stabilizes magnetic sensors v d e Periodic table H   He Li Be   B C N O F Ne Na Mg   Al Si P S Cl Ar K Ca   Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr   Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Uuq Uup Uuh Uus Uuo Alkali metals Alkaline earth metals Lanthanides Actinides Transition metals Other metals Metalloids Other nonmetals Halogens Noble gases Unknown chem. properties Large version  v d e  Ruthenium compounds RuB2  RuO2  RuCl3  RuO4  N(C3H7)4RuO4  C72H42N6Na4O18RuS6  Ru3(CO)12  (Ru(bipy)3)Cl2  C62H42O6Ru2  C54H45Cl2P3Ru  C8H24Cl2O4RuS4  C56H45O2P3Ru    C20H28Cl4Ru2  C41H35ClP2Ru  (C5H5)2Ru v d eChemical elements named after places Named after terrestrial places Magnesium   Scandium   Copper   Gallium   Germanium   Strontium   Yttrium   Ruthenium   Tellurium   Europium   Terbium   Holmium   Erbium   Thulium   Ytterbium   Lutetium   Hafnium   Rhenium   Polonium   Francium   Americium   Berkelium   Californium   Dubnium   Hassium   Darmstadtium Named after astronomical objects Helium   Selenium  Palladium   Cerium   Uranium   Neptunium   Plutonium